This invention relates generally to automotive vehicle convertible roofs and more particularly to a convertible roof bow tensioning apparatus.
Traditional soft-top convertible roofs for automotive vehicles typically employ four or five roof bows spanning transversely across the vehicle for supporting a vinyl, canvas or polyester fiber, pliable roof cover. The roof bows extend between foldable side rails which can be automatically or manually raised and lowered. Many conventional soft-top convertible roofs inherently drift due to the stretched fabric cover pulling the forwardmost number one roof bow in an unintended and undesired rearward direction away from the front header when the roof is raised. This drifting situation is especially apparent in new convertible roofs or in cold weather. Accordingly, the vehicle occupant must then physically pull down upon a handle attached to the number one roof bow and hold it against the front header panel for subsequent manual latching, or an automated latch is employed with a difficult to package, extended reach. This drifting problem is also present between a rearmost or number five roof bow and an adjacent tonneau cover, when a hard-tonneau cover is employed to cover the convertible roof boot well. The stretched fabric cover tends to pull the number five roof bow in a forward manner thereby causing it to drift away from the mating tonneau cover. This five bow drift situation is inconvenient to remedy due to the difficulty of an occupant accessing this rear area when seated in the front seat.
Notwithstanding, the following U.S. patents disclose various systems which attempt to minimize the drift concern: U.S. Pat. No. 5,998,948 entitled “Convertible Roof Actuation Mechanism” which issued to Lange et al. on Dec. 7, 1999; U.S. Pat. No. 5,903,119 entitled “Convertible Roof Actuation Mechanism” which issued to Laurain et al. on May 11, 1999; and U.S. Pat. No. 5,385,381 entitled “Vehicle Roofs” which issued to Moore et al. on Jan. 31, 1995; these patents are incorporated by reference herein. While the Lange et al. and Laurain et al. patents are significant improvements in the field, further refinement of a convertible roof bow tensioning configuration is desirable in order to reduce packaging size and cost while improving performance and locational placement.
In accordance with the present invention, the preferred embodiment of a convertible roof bow tensioning apparatus includes a pliable roof cover, a top stack mechanism supporting the roof cover having at least one roof bow, and a roof bow tensioner for selectively reducing and increasing tension of the roof cover. Another aspect of the present invention provides a camming apparatus operably extending and retracting a roof bow relative to a remainder of a convertible top stack mechanism. In a further aspect of the present invention, a tensioning number two bow, three bow, four bow and/or five bow are provided. Still another aspect of the present invention employs a linearly moving apparatus operable to make a convertible roof cover taut and slack in order to reduce convertible roof drift.
The convertible roof bow tensioning apparatus of the present invention is advantageous over conventional constructions in that the present invention reduces drift of the raised convertible roof away from the front header panel and, alternately a tonneau cover, by selectively reducing and then increasing tension or tautness of the roof cover. Furthermore, packaging space of the stowed convertible roof is optimized in the storage compartment by selected reduction in height of a roof bow. Another advantage of the present invention is employment of the tensioner in tight packaging spaces for use with a number two bow or a number three bow, although it may also provide movement to a number four or five roof bow. Moreover, the present invention advantageously provides relatively simple mechanisms and movement directions (such as linear movement) thereby advantageously being easier to design, package and refine during assembly or for service. Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.